xref: /openbmc/qemu/net/net.c (revision 56e6f594)
1 /*
2  * QEMU System Emulator
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 #include "qemu-common.h"
27 
28 #include "net/net.h"
29 #include "clients.h"
30 #include "hub.h"
31 #include "hw/qdev-properties.h"
32 #include "net/slirp.h"
33 #include "net/eth.h"
34 #include "util.h"
35 
36 #include "monitor/monitor.h"
37 #include "qemu/help_option.h"
38 #include "qapi/qapi-commands-net.h"
39 #include "qapi/qmp/qdict.h"
40 #include "qapi/qmp/qerror.h"
41 #include "qemu/error-report.h"
42 #include "qemu/sockets.h"
43 #include "qemu/cutils.h"
44 #include "qemu/config-file.h"
45 #include "qemu/ctype.h"
46 #include "qemu/id.h"
47 #include "qemu/iov.h"
48 #include "qemu/qemu-print.h"
49 #include "qemu/main-loop.h"
50 #include "qemu/option.h"
51 #include "qapi/error.h"
52 #include "qapi/opts-visitor.h"
53 #include "sysemu/sysemu.h"
54 #include "sysemu/runstate.h"
55 #include "sysemu/sysemu.h"
56 #include "net/filter.h"
57 #include "qapi/string-output-visitor.h"
58 
59 /* Net bridge is currently not supported for W32. */
60 #if !defined(_WIN32)
61 # define CONFIG_NET_BRIDGE
62 #endif
63 
64 static VMChangeStateEntry *net_change_state_entry;
65 static QTAILQ_HEAD(, NetClientState) net_clients;
66 
67 /***********************************************************/
68 /* network device redirectors */
69 
70 int parse_host_port(struct sockaddr_in *saddr, const char *str,
71                     Error **errp)
72 {
73     gchar **substrings;
74     struct hostent *he;
75     const char *addr, *p, *r;
76     int port, ret = 0;
77 
78     substrings = g_strsplit(str, ":", 2);
79     if (!substrings || !substrings[0] || !substrings[1]) {
80         error_setg(errp, "host address '%s' doesn't contain ':' "
81                    "separating host from port", str);
82         ret = -1;
83         goto out;
84     }
85 
86     addr = substrings[0];
87     p = substrings[1];
88 
89     saddr->sin_family = AF_INET;
90     if (addr[0] == '\0') {
91         saddr->sin_addr.s_addr = 0;
92     } else {
93         if (qemu_isdigit(addr[0])) {
94             if (!inet_aton(addr, &saddr->sin_addr)) {
95                 error_setg(errp, "host address '%s' is not a valid "
96                            "IPv4 address", addr);
97                 ret = -1;
98                 goto out;
99             }
100         } else {
101             he = gethostbyname(addr);
102             if (he == NULL) {
103                 error_setg(errp, "can't resolve host address '%s'", addr);
104                 ret = -1;
105                 goto out;
106             }
107             saddr->sin_addr = *(struct in_addr *)he->h_addr;
108         }
109     }
110     port = strtol(p, (char **)&r, 0);
111     if (r == p) {
112         error_setg(errp, "port number '%s' is invalid", p);
113         ret = -1;
114         goto out;
115     }
116     saddr->sin_port = htons(port);
117 
118 out:
119     g_strfreev(substrings);
120     return ret;
121 }
122 
123 char *qemu_mac_strdup_printf(const uint8_t *macaddr)
124 {
125     return g_strdup_printf("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
126                            macaddr[0], macaddr[1], macaddr[2],
127                            macaddr[3], macaddr[4], macaddr[5]);
128 }
129 
130 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
131 {
132     snprintf(nc->info_str, sizeof(nc->info_str),
133              "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
134              nc->model,
135              macaddr[0], macaddr[1], macaddr[2],
136              macaddr[3], macaddr[4], macaddr[5]);
137 }
138 
139 static int mac_table[256] = {0};
140 
141 static void qemu_macaddr_set_used(MACAddr *macaddr)
142 {
143     int index;
144 
145     for (index = 0x56; index < 0xFF; index++) {
146         if (macaddr->a[5] == index) {
147             mac_table[index]++;
148         }
149     }
150 }
151 
152 static void qemu_macaddr_set_free(MACAddr *macaddr)
153 {
154     int index;
155     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
156 
157     if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
158         return;
159     }
160     for (index = 0x56; index < 0xFF; index++) {
161         if (macaddr->a[5] == index) {
162             mac_table[index]--;
163         }
164     }
165 }
166 
167 static int qemu_macaddr_get_free(void)
168 {
169     int index;
170 
171     for (index = 0x56; index < 0xFF; index++) {
172         if (mac_table[index] == 0) {
173             return index;
174         }
175     }
176 
177     return -1;
178 }
179 
180 void qemu_macaddr_default_if_unset(MACAddr *macaddr)
181 {
182     static const MACAddr zero = { .a = { 0,0,0,0,0,0 } };
183     static const MACAddr base = { .a = { 0x52, 0x54, 0x00, 0x12, 0x34, 0 } };
184 
185     if (memcmp(macaddr, &zero, sizeof(zero)) != 0) {
186         if (memcmp(macaddr->a, &base.a, (sizeof(base.a) - 1)) != 0) {
187             return;
188         } else {
189             qemu_macaddr_set_used(macaddr);
190             return;
191         }
192     }
193 
194     macaddr->a[0] = 0x52;
195     macaddr->a[1] = 0x54;
196     macaddr->a[2] = 0x00;
197     macaddr->a[3] = 0x12;
198     macaddr->a[4] = 0x34;
199     macaddr->a[5] = qemu_macaddr_get_free();
200     qemu_macaddr_set_used(macaddr);
201 }
202 
203 /**
204  * Generate a name for net client
205  *
206  * Only net clients created with the legacy -net option and NICs need this.
207  */
208 static char *assign_name(NetClientState *nc1, const char *model)
209 {
210     NetClientState *nc;
211     int id = 0;
212 
213     QTAILQ_FOREACH(nc, &net_clients, next) {
214         if (nc == nc1) {
215             continue;
216         }
217         if (strcmp(nc->model, model) == 0) {
218             id++;
219         }
220     }
221 
222     return g_strdup_printf("%s.%d", model, id);
223 }
224 
225 static void qemu_net_client_destructor(NetClientState *nc)
226 {
227     g_free(nc);
228 }
229 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
230                                        unsigned flags,
231                                        const struct iovec *iov,
232                                        int iovcnt,
233                                        void *opaque);
234 
235 static void qemu_net_client_setup(NetClientState *nc,
236                                   NetClientInfo *info,
237                                   NetClientState *peer,
238                                   const char *model,
239                                   const char *name,
240                                   NetClientDestructor *destructor)
241 {
242     nc->info = info;
243     nc->model = g_strdup(model);
244     if (name) {
245         nc->name = g_strdup(name);
246     } else {
247         nc->name = assign_name(nc, model);
248     }
249 
250     if (peer) {
251         assert(!peer->peer);
252         nc->peer = peer;
253         peer->peer = nc;
254     }
255     QTAILQ_INSERT_TAIL(&net_clients, nc, next);
256 
257     nc->incoming_queue = qemu_new_net_queue(qemu_deliver_packet_iov, nc);
258     nc->destructor = destructor;
259     QTAILQ_INIT(&nc->filters);
260 }
261 
262 NetClientState *qemu_new_net_client(NetClientInfo *info,
263                                     NetClientState *peer,
264                                     const char *model,
265                                     const char *name)
266 {
267     NetClientState *nc;
268 
269     assert(info->size >= sizeof(NetClientState));
270 
271     nc = g_malloc0(info->size);
272     qemu_net_client_setup(nc, info, peer, model, name,
273                           qemu_net_client_destructor);
274 
275     return nc;
276 }
277 
278 NICState *qemu_new_nic(NetClientInfo *info,
279                        NICConf *conf,
280                        const char *model,
281                        const char *name,
282                        void *opaque)
283 {
284     NetClientState **peers = conf->peers.ncs;
285     NICState *nic;
286     int i, queues = MAX(1, conf->peers.queues);
287 
288     assert(info->type == NET_CLIENT_DRIVER_NIC);
289     assert(info->size >= sizeof(NICState));
290 
291     nic = g_malloc0(info->size + sizeof(NetClientState) * queues);
292     nic->ncs = (void *)nic + info->size;
293     nic->conf = conf;
294     nic->opaque = opaque;
295 
296     for (i = 0; i < queues; i++) {
297         qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, name,
298                               NULL);
299         nic->ncs[i].queue_index = i;
300     }
301 
302     return nic;
303 }
304 
305 NetClientState *qemu_get_subqueue(NICState *nic, int queue_index)
306 {
307     return nic->ncs + queue_index;
308 }
309 
310 NetClientState *qemu_get_queue(NICState *nic)
311 {
312     return qemu_get_subqueue(nic, 0);
313 }
314 
315 NICState *qemu_get_nic(NetClientState *nc)
316 {
317     NetClientState *nc0 = nc - nc->queue_index;
318 
319     return (NICState *)((void *)nc0 - nc->info->size);
320 }
321 
322 void *qemu_get_nic_opaque(NetClientState *nc)
323 {
324     NICState *nic = qemu_get_nic(nc);
325 
326     return nic->opaque;
327 }
328 
329 NetClientState *qemu_get_peer(NetClientState *nc, int queue_index)
330 {
331     assert(nc != NULL);
332     NetClientState *ncs = nc + queue_index;
333     return ncs->peer;
334 }
335 
336 static void qemu_cleanup_net_client(NetClientState *nc)
337 {
338     QTAILQ_REMOVE(&net_clients, nc, next);
339 
340     if (nc->info->cleanup) {
341         nc->info->cleanup(nc);
342     }
343 }
344 
345 static void qemu_free_net_client(NetClientState *nc)
346 {
347     if (nc->incoming_queue) {
348         qemu_del_net_queue(nc->incoming_queue);
349     }
350     if (nc->peer) {
351         nc->peer->peer = NULL;
352     }
353     g_free(nc->name);
354     g_free(nc->model);
355     qapi_free_NetdevInfo(nc->stored_config);
356     if (nc->destructor) {
357         nc->destructor(nc);
358     }
359 }
360 
361 void qemu_del_net_client(NetClientState *nc)
362 {
363     NetClientState *ncs[MAX_QUEUE_NUM];
364     int queues, i;
365     NetFilterState *nf, *next;
366 
367     assert(nc->info->type != NET_CLIENT_DRIVER_NIC);
368 
369     /* If the NetClientState belongs to a multiqueue backend, we will change all
370      * other NetClientStates also.
371      */
372     queues = qemu_find_net_clients_except(nc->name, ncs,
373                                           NET_CLIENT_DRIVER_NIC,
374                                           MAX_QUEUE_NUM);
375     assert(queues != 0);
376 
377     QTAILQ_FOREACH_SAFE(nf, &nc->filters, next, next) {
378         object_unparent(OBJECT(nf));
379     }
380 
381     /* If there is a peer NIC, delete and cleanup client, but do not free. */
382     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
383         NICState *nic = qemu_get_nic(nc->peer);
384         if (nic->peer_deleted) {
385             return;
386         }
387         nic->peer_deleted = true;
388 
389         for (i = 0; i < queues; i++) {
390             ncs[i]->peer->link_down = true;
391         }
392 
393         if (nc->peer->info->link_status_changed) {
394             nc->peer->info->link_status_changed(nc->peer);
395         }
396 
397         for (i = 0; i < queues; i++) {
398             qemu_cleanup_net_client(ncs[i]);
399         }
400 
401         return;
402     }
403 
404     for (i = 0; i < queues; i++) {
405         qemu_cleanup_net_client(ncs[i]);
406         qemu_free_net_client(ncs[i]);
407     }
408 }
409 
410 void qemu_del_nic(NICState *nic)
411 {
412     int i, queues = MAX(nic->conf->peers.queues, 1);
413 
414     qemu_macaddr_set_free(&nic->conf->macaddr);
415 
416     for (i = 0; i < queues; i++) {
417         NetClientState *nc = qemu_get_subqueue(nic, i);
418         /* If this is a peer NIC and peer has already been deleted, free it now. */
419         if (nic->peer_deleted) {
420             qemu_free_net_client(nc->peer);
421         } else if (nc->peer) {
422             /* if there are RX packets pending, complete them */
423             qemu_purge_queued_packets(nc->peer);
424         }
425     }
426 
427     for (i = queues - 1; i >= 0; i--) {
428         NetClientState *nc = qemu_get_subqueue(nic, i);
429 
430         qemu_cleanup_net_client(nc);
431         qemu_free_net_client(nc);
432     }
433 
434     g_free(nic);
435 }
436 
437 void qemu_foreach_nic(qemu_nic_foreach func, void *opaque)
438 {
439     NetClientState *nc;
440 
441     QTAILQ_FOREACH(nc, &net_clients, next) {
442         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
443             if (nc->queue_index == 0) {
444                 func(qemu_get_nic(nc), opaque);
445             }
446         }
447     }
448 }
449 
450 bool qemu_has_ufo(NetClientState *nc)
451 {
452     if (!nc || !nc->info->has_ufo) {
453         return false;
454     }
455 
456     return nc->info->has_ufo(nc);
457 }
458 
459 bool qemu_has_vnet_hdr(NetClientState *nc)
460 {
461     if (!nc || !nc->info->has_vnet_hdr) {
462         return false;
463     }
464 
465     return nc->info->has_vnet_hdr(nc);
466 }
467 
468 bool qemu_has_vnet_hdr_len(NetClientState *nc, int len)
469 {
470     if (!nc || !nc->info->has_vnet_hdr_len) {
471         return false;
472     }
473 
474     return nc->info->has_vnet_hdr_len(nc, len);
475 }
476 
477 void qemu_using_vnet_hdr(NetClientState *nc, bool enable)
478 {
479     if (!nc || !nc->info->using_vnet_hdr) {
480         return;
481     }
482 
483     nc->info->using_vnet_hdr(nc, enable);
484 }
485 
486 void qemu_set_offload(NetClientState *nc, int csum, int tso4, int tso6,
487                           int ecn, int ufo)
488 {
489     if (!nc || !nc->info->set_offload) {
490         return;
491     }
492 
493     nc->info->set_offload(nc, csum, tso4, tso6, ecn, ufo);
494 }
495 
496 void qemu_set_vnet_hdr_len(NetClientState *nc, int len)
497 {
498     if (!nc || !nc->info->set_vnet_hdr_len) {
499         return;
500     }
501 
502     nc->vnet_hdr_len = len;
503     nc->info->set_vnet_hdr_len(nc, len);
504 }
505 
506 int qemu_set_vnet_le(NetClientState *nc, bool is_le)
507 {
508 #ifdef HOST_WORDS_BIGENDIAN
509     if (!nc || !nc->info->set_vnet_le) {
510         return -ENOSYS;
511     }
512 
513     return nc->info->set_vnet_le(nc, is_le);
514 #else
515     return 0;
516 #endif
517 }
518 
519 int qemu_set_vnet_be(NetClientState *nc, bool is_be)
520 {
521 #ifdef HOST_WORDS_BIGENDIAN
522     return 0;
523 #else
524     if (!nc || !nc->info->set_vnet_be) {
525         return -ENOSYS;
526     }
527 
528     return nc->info->set_vnet_be(nc, is_be);
529 #endif
530 }
531 
532 int qemu_can_receive_packet(NetClientState *nc)
533 {
534     if (nc->receive_disabled) {
535         return 0;
536     } else if (nc->info->can_receive &&
537                !nc->info->can_receive(nc)) {
538         return 0;
539     }
540     return 1;
541 }
542 
543 int qemu_can_send_packet(NetClientState *sender)
544 {
545     int vm_running = runstate_is_running();
546 
547     if (!vm_running) {
548         return 0;
549     }
550 
551     if (!sender->peer) {
552         return 1;
553     }
554 
555     return qemu_can_receive_packet(sender->peer);
556 }
557 
558 static ssize_t filter_receive_iov(NetClientState *nc,
559                                   NetFilterDirection direction,
560                                   NetClientState *sender,
561                                   unsigned flags,
562                                   const struct iovec *iov,
563                                   int iovcnt,
564                                   NetPacketSent *sent_cb)
565 {
566     ssize_t ret = 0;
567     NetFilterState *nf = NULL;
568 
569     if (direction == NET_FILTER_DIRECTION_TX) {
570         QTAILQ_FOREACH(nf, &nc->filters, next) {
571             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
572                                          iovcnt, sent_cb);
573             if (ret) {
574                 return ret;
575             }
576         }
577     } else {
578         QTAILQ_FOREACH_REVERSE(nf, &nc->filters, next) {
579             ret = qemu_netfilter_receive(nf, direction, sender, flags, iov,
580                                          iovcnt, sent_cb);
581             if (ret) {
582                 return ret;
583             }
584         }
585     }
586 
587     return ret;
588 }
589 
590 static ssize_t filter_receive(NetClientState *nc,
591                               NetFilterDirection direction,
592                               NetClientState *sender,
593                               unsigned flags,
594                               const uint8_t *data,
595                               size_t size,
596                               NetPacketSent *sent_cb)
597 {
598     struct iovec iov = {
599         .iov_base = (void *)data,
600         .iov_len = size
601     };
602 
603     return filter_receive_iov(nc, direction, sender, flags, &iov, 1, sent_cb);
604 }
605 
606 void qemu_purge_queued_packets(NetClientState *nc)
607 {
608     if (!nc->peer) {
609         return;
610     }
611 
612     qemu_net_queue_purge(nc->peer->incoming_queue, nc);
613 }
614 
615 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge)
616 {
617     nc->receive_disabled = 0;
618 
619     if (nc->peer && nc->peer->info->type == NET_CLIENT_DRIVER_HUBPORT) {
620         if (net_hub_flush(nc->peer)) {
621             qemu_notify_event();
622         }
623     }
624     if (qemu_net_queue_flush(nc->incoming_queue)) {
625         /* We emptied the queue successfully, signal to the IO thread to repoll
626          * the file descriptor (for tap, for example).
627          */
628         qemu_notify_event();
629     } else if (purge) {
630         /* Unable to empty the queue, purge remaining packets */
631         qemu_net_queue_purge(nc->incoming_queue, nc->peer);
632     }
633 }
634 
635 void qemu_flush_queued_packets(NetClientState *nc)
636 {
637     qemu_flush_or_purge_queued_packets(nc, false);
638 }
639 
640 static ssize_t qemu_send_packet_async_with_flags(NetClientState *sender,
641                                                  unsigned flags,
642                                                  const uint8_t *buf, int size,
643                                                  NetPacketSent *sent_cb)
644 {
645     NetQueue *queue;
646     int ret;
647 
648 #ifdef DEBUG_NET
649     printf("qemu_send_packet_async:\n");
650     qemu_hexdump(stdout, "net", buf, size);
651 #endif
652 
653     if (sender->link_down || !sender->peer) {
654         return size;
655     }
656 
657     /* Let filters handle the packet first */
658     ret = filter_receive(sender, NET_FILTER_DIRECTION_TX,
659                          sender, flags, buf, size, sent_cb);
660     if (ret) {
661         return ret;
662     }
663 
664     ret = filter_receive(sender->peer, NET_FILTER_DIRECTION_RX,
665                          sender, flags, buf, size, sent_cb);
666     if (ret) {
667         return ret;
668     }
669 
670     queue = sender->peer->incoming_queue;
671 
672     return qemu_net_queue_send(queue, sender, flags, buf, size, sent_cb);
673 }
674 
675 ssize_t qemu_send_packet_async(NetClientState *sender,
676                                const uint8_t *buf, int size,
677                                NetPacketSent *sent_cb)
678 {
679     return qemu_send_packet_async_with_flags(sender, QEMU_NET_PACKET_FLAG_NONE,
680                                              buf, size, sent_cb);
681 }
682 
683 ssize_t qemu_send_packet(NetClientState *nc, const uint8_t *buf, int size)
684 {
685     return qemu_send_packet_async(nc, buf, size, NULL);
686 }
687 
688 ssize_t qemu_receive_packet(NetClientState *nc, const uint8_t *buf, int size)
689 {
690     if (!qemu_can_receive_packet(nc)) {
691         return 0;
692     }
693 
694     return qemu_net_queue_receive(nc->incoming_queue, buf, size);
695 }
696 
697 ssize_t qemu_receive_packet_iov(NetClientState *nc, const struct iovec *iov,
698                                 int iovcnt)
699 {
700     if (!qemu_can_receive_packet(nc)) {
701         return 0;
702     }
703 
704     return qemu_net_queue_receive_iov(nc->incoming_queue, iov, iovcnt);
705 }
706 
707 ssize_t qemu_send_packet_raw(NetClientState *nc, const uint8_t *buf, int size)
708 {
709     return qemu_send_packet_async_with_flags(nc, QEMU_NET_PACKET_FLAG_RAW,
710                                              buf, size, NULL);
711 }
712 
713 static ssize_t nc_sendv_compat(NetClientState *nc, const struct iovec *iov,
714                                int iovcnt, unsigned flags)
715 {
716     uint8_t *buf = NULL;
717     uint8_t *buffer;
718     size_t offset;
719     ssize_t ret;
720 
721     if (iovcnt == 1) {
722         buffer = iov[0].iov_base;
723         offset = iov[0].iov_len;
724     } else {
725         offset = iov_size(iov, iovcnt);
726         if (offset > NET_BUFSIZE) {
727             return -1;
728         }
729         buf = g_malloc(offset);
730         buffer = buf;
731         offset = iov_to_buf(iov, iovcnt, 0, buf, offset);
732     }
733 
734     if (flags & QEMU_NET_PACKET_FLAG_RAW && nc->info->receive_raw) {
735         ret = nc->info->receive_raw(nc, buffer, offset);
736     } else {
737         ret = nc->info->receive(nc, buffer, offset);
738     }
739 
740     g_free(buf);
741     return ret;
742 }
743 
744 static ssize_t qemu_deliver_packet_iov(NetClientState *sender,
745                                        unsigned flags,
746                                        const struct iovec *iov,
747                                        int iovcnt,
748                                        void *opaque)
749 {
750     NetClientState *nc = opaque;
751     int ret;
752 
753 
754     if (nc->link_down) {
755         return iov_size(iov, iovcnt);
756     }
757 
758     if (nc->receive_disabled) {
759         return 0;
760     }
761 
762     if (nc->info->receive_iov && !(flags & QEMU_NET_PACKET_FLAG_RAW)) {
763         ret = nc->info->receive_iov(nc, iov, iovcnt);
764     } else {
765         ret = nc_sendv_compat(nc, iov, iovcnt, flags);
766     }
767 
768     if (ret == 0) {
769         nc->receive_disabled = 1;
770     }
771 
772     return ret;
773 }
774 
775 ssize_t qemu_sendv_packet_async(NetClientState *sender,
776                                 const struct iovec *iov, int iovcnt,
777                                 NetPacketSent *sent_cb)
778 {
779     NetQueue *queue;
780     size_t size = iov_size(iov, iovcnt);
781     int ret;
782 
783     if (size > NET_BUFSIZE) {
784         return size;
785     }
786 
787     if (sender->link_down || !sender->peer) {
788         return size;
789     }
790 
791     /* Let filters handle the packet first */
792     ret = filter_receive_iov(sender, NET_FILTER_DIRECTION_TX, sender,
793                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
794     if (ret) {
795         return ret;
796     }
797 
798     ret = filter_receive_iov(sender->peer, NET_FILTER_DIRECTION_RX, sender,
799                              QEMU_NET_PACKET_FLAG_NONE, iov, iovcnt, sent_cb);
800     if (ret) {
801         return ret;
802     }
803 
804     queue = sender->peer->incoming_queue;
805 
806     return qemu_net_queue_send_iov(queue, sender,
807                                    QEMU_NET_PACKET_FLAG_NONE,
808                                    iov, iovcnt, sent_cb);
809 }
810 
811 ssize_t
812 qemu_sendv_packet(NetClientState *nc, const struct iovec *iov, int iovcnt)
813 {
814     return qemu_sendv_packet_async(nc, iov, iovcnt, NULL);
815 }
816 
817 NetClientState *qemu_find_netdev(const char *id)
818 {
819     NetClientState *nc;
820 
821     QTAILQ_FOREACH(nc, &net_clients, next) {
822         if (nc->info->type == NET_CLIENT_DRIVER_NIC)
823             continue;
824         if (!strcmp(nc->name, id)) {
825             return nc;
826         }
827     }
828 
829     return NULL;
830 }
831 
832 int qemu_find_net_clients_except(const char *id, NetClientState **ncs,
833                                  NetClientDriver type, int max)
834 {
835     NetClientState *nc;
836     int ret = 0;
837 
838     QTAILQ_FOREACH(nc, &net_clients, next) {
839         if (nc->info->type == type) {
840             continue;
841         }
842         if (!id || !strcmp(nc->name, id)) {
843             if (ret < max) {
844                 ncs[ret] = nc;
845             }
846             ret++;
847         }
848     }
849 
850     return ret;
851 }
852 
853 static int nic_get_free_idx(void)
854 {
855     int index;
856 
857     for (index = 0; index < MAX_NICS; index++)
858         if (!nd_table[index].used)
859             return index;
860     return -1;
861 }
862 
863 int qemu_show_nic_models(const char *arg, const char *const *models)
864 {
865     int i;
866 
867     if (!arg || !is_help_option(arg)) {
868         return 0;
869     }
870 
871     printf("Supported NIC models:\n");
872     for (i = 0 ; models[i]; i++) {
873         printf("%s\n", models[i]);
874     }
875     return 1;
876 }
877 
878 void qemu_check_nic_model(NICInfo *nd, const char *model)
879 {
880     const char *models[2];
881 
882     models[0] = model;
883     models[1] = NULL;
884 
885     if (qemu_show_nic_models(nd->model, models))
886         exit(0);
887     if (qemu_find_nic_model(nd, models, model) < 0)
888         exit(1);
889 }
890 
891 int qemu_find_nic_model(NICInfo *nd, const char * const *models,
892                         const char *default_model)
893 {
894     int i;
895 
896     if (!nd->model)
897         nd->model = g_strdup(default_model);
898 
899     for (i = 0 ; models[i]; i++) {
900         if (strcmp(nd->model, models[i]) == 0)
901             return i;
902     }
903 
904     error_report("Unsupported NIC model: %s", nd->model);
905     return -1;
906 }
907 
908 static int net_init_nic(const Netdev *netdev, const char *name,
909                         NetClientState *peer, Error **errp)
910 {
911     int idx;
912     NICInfo *nd;
913     const NetLegacyNicOptions *nic;
914 
915     assert(netdev->type == NET_CLIENT_DRIVER_NIC);
916     nic = &netdev->u.nic;
917 
918     idx = nic_get_free_idx();
919     if (idx == -1 || nb_nics >= MAX_NICS) {
920         error_setg(errp, "too many NICs");
921         return -1;
922     }
923 
924     nd = &nd_table[idx];
925 
926     memset(nd, 0, sizeof(*nd));
927 
928     if (nic->has_netdev) {
929         nd->netdev = qemu_find_netdev(nic->netdev);
930         if (!nd->netdev) {
931             error_setg(errp, "netdev '%s' not found", nic->netdev);
932             return -1;
933         }
934     } else {
935         assert(peer);
936         nd->netdev = peer;
937     }
938     nd->name = g_strdup(name);
939     if (nic->has_model) {
940         nd->model = g_strdup(nic->model);
941     }
942     if (nic->has_addr) {
943         nd->devaddr = g_strdup(nic->addr);
944     }
945 
946     if (nic->has_macaddr &&
947         net_parse_macaddr(nd->macaddr.a, nic->macaddr) < 0) {
948         error_setg(errp, "invalid syntax for ethernet address");
949         return -1;
950     }
951     if (nic->has_macaddr &&
952         is_multicast_ether_addr(nd->macaddr.a)) {
953         error_setg(errp,
954                    "NIC cannot have multicast MAC address (odd 1st byte)");
955         return -1;
956     }
957     qemu_macaddr_default_if_unset(&nd->macaddr);
958 
959     if (nic->has_vectors) {
960         if (nic->vectors > 0x7ffffff) {
961             error_setg(errp, "invalid # of vectors: %"PRIu32, nic->vectors);
962             return -1;
963         }
964         nd->nvectors = nic->vectors;
965     } else {
966         nd->nvectors = DEV_NVECTORS_UNSPECIFIED;
967     }
968 
969     nd->used = 1;
970     nb_nics++;
971 
972     return idx;
973 }
974 
975 
976 static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
977     const Netdev *netdev,
978     const char *name,
979     NetClientState *peer, Error **errp) = {
980         [NET_CLIENT_DRIVER_NIC]       = net_init_nic,
981 #ifdef CONFIG_SLIRP
982         [NET_CLIENT_DRIVER_USER]      = net_init_slirp,
983 #endif
984         [NET_CLIENT_DRIVER_TAP]       = net_init_tap,
985         [NET_CLIENT_DRIVER_SOCKET]    = net_init_socket,
986 #ifdef CONFIG_VDE
987         [NET_CLIENT_DRIVER_VDE]       = net_init_vde,
988 #endif
989 #ifdef CONFIG_NETMAP
990         [NET_CLIENT_DRIVER_NETMAP]    = net_init_netmap,
991 #endif
992 #ifdef CONFIG_NET_BRIDGE
993         [NET_CLIENT_DRIVER_BRIDGE]    = net_init_bridge,
994 #endif
995         [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
996 #ifdef CONFIG_VHOST_NET_USER
997         [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
998 #endif
999 #ifdef CONFIG_VHOST_NET_VDPA
1000         [NET_CLIENT_DRIVER_VHOST_VDPA] = net_init_vhost_vdpa,
1001 #endif
1002 #ifdef CONFIG_L2TPV3
1003         [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
1004 #endif
1005 };
1006 
1007 
1008 static int net_client_init1(const Netdev *netdev, bool is_netdev, Error **errp)
1009 {
1010     NetClientState *peer = NULL;
1011     NetClientState *nc;
1012 
1013     if (is_netdev) {
1014         if (netdev->type == NET_CLIENT_DRIVER_NIC ||
1015             !net_client_init_fun[netdev->type]) {
1016             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1017                        "a netdev backend type");
1018             return -1;
1019         }
1020     } else {
1021         if (netdev->type == NET_CLIENT_DRIVER_NONE) {
1022             return 0; /* nothing to do */
1023         }
1024         if (netdev->type == NET_CLIENT_DRIVER_HUBPORT ||
1025             !net_client_init_fun[netdev->type]) {
1026             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "type",
1027                        "a net backend type (maybe it is not compiled "
1028                        "into this binary)");
1029             return -1;
1030         }
1031 
1032         /* Do not add to a hub if it's a nic with a netdev= parameter. */
1033         if (netdev->type != NET_CLIENT_DRIVER_NIC ||
1034             !netdev->u.nic.has_netdev) {
1035             peer = net_hub_add_port(0, NULL, NULL);
1036         }
1037     }
1038 
1039     nc = qemu_find_netdev(netdev->id);
1040     if (nc) {
1041         error_setg(errp, "Duplicate ID '%s'", netdev->id);
1042         return -1;
1043     }
1044 
1045     if (net_client_init_fun[netdev->type](netdev, netdev->id, peer, errp) < 0) {
1046         /* FIXME drop when all init functions store an Error */
1047         if (errp && !*errp) {
1048             error_setg(errp, "Device '%s' could not be initialized",
1049                        NetClientDriver_str(netdev->type));
1050         }
1051         return -1;
1052     }
1053 
1054     if (is_netdev) {
1055         nc = qemu_find_netdev(netdev->id);
1056         assert(nc);
1057         nc->is_netdev = true;
1058     }
1059 
1060     return 0;
1061 }
1062 
1063 void show_netdevs(void)
1064 {
1065     int idx;
1066     const char *available_netdevs[] = {
1067         "socket",
1068         "hubport",
1069         "tap",
1070 #ifdef CONFIG_SLIRP
1071         "user",
1072 #endif
1073 #ifdef CONFIG_L2TPV3
1074         "l2tpv3",
1075 #endif
1076 #ifdef CONFIG_VDE
1077         "vde",
1078 #endif
1079 #ifdef CONFIG_NET_BRIDGE
1080         "bridge",
1081 #endif
1082 #ifdef CONFIG_NETMAP
1083         "netmap",
1084 #endif
1085 #ifdef CONFIG_POSIX
1086         "vhost-user",
1087 #endif
1088 #ifdef CONFIG_VHOST_VDPA
1089         "vhost-vdpa",
1090 #endif
1091     };
1092 
1093     qemu_printf("Available netdev backend types:\n");
1094     for (idx = 0; idx < ARRAY_SIZE(available_netdevs); idx++) {
1095         qemu_printf("%s\n", available_netdevs[idx]);
1096     }
1097 }
1098 
1099 static int net_client_init(QemuOpts *opts, bool is_netdev, Error **errp)
1100 {
1101     gchar **substrings = NULL;
1102     Netdev *object = NULL;
1103     int ret = -1;
1104     Visitor *v = opts_visitor_new(opts);
1105 
1106     /* Parse convenience option format ip6-net=fec0::0[/64] */
1107     const char *ip6_net = qemu_opt_get(opts, "ipv6-net");
1108 
1109     if (ip6_net) {
1110         char *prefix_addr;
1111         unsigned long prefix_len = 64; /* Default 64bit prefix length. */
1112 
1113         substrings = g_strsplit(ip6_net, "/", 2);
1114         if (!substrings || !substrings[0]) {
1115             error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "ipv6-net",
1116                        "a valid IPv6 prefix");
1117             goto out;
1118         }
1119 
1120         prefix_addr = substrings[0];
1121 
1122         /* Handle user-specified prefix length. */
1123         if (substrings[1] &&
1124             qemu_strtoul(substrings[1], NULL, 10, &prefix_len))
1125         {
1126             error_setg(errp, QERR_INVALID_PARAMETER_VALUE,
1127                        "ipv6-prefixlen", "a number");
1128             goto out;
1129         }
1130 
1131         qemu_opt_set(opts, "ipv6-prefix", prefix_addr, &error_abort);
1132         qemu_opt_set_number(opts, "ipv6-prefixlen", prefix_len,
1133                             &error_abort);
1134         qemu_opt_unset(opts, "ipv6-net");
1135     }
1136 
1137     /* Create an ID for -net if the user did not specify one */
1138     if (!is_netdev && !qemu_opts_id(opts)) {
1139         qemu_opts_set_id(opts, id_generate(ID_NET));
1140     }
1141 
1142     if (visit_type_Netdev(v, NULL, &object, errp)) {
1143         ret = net_client_init1(object, is_netdev, errp);
1144     }
1145 
1146     qapi_free_Netdev(object);
1147 
1148 out:
1149     g_strfreev(substrings);
1150     visit_free(v);
1151     return ret;
1152 }
1153 
1154 void netdev_add(QemuOpts *opts, Error **errp)
1155 {
1156     net_client_init(opts, true, errp);
1157 }
1158 
1159 void qmp_netdev_add(Netdev *netdev, Error **errp)
1160 {
1161     if (!id_wellformed(netdev->id)) {
1162         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "id", "an identifier");
1163         return;
1164     }
1165 
1166     net_client_init1(netdev, true, errp);
1167 }
1168 
1169 void qmp_netdev_del(const char *id, Error **errp)
1170 {
1171     NetClientState *nc;
1172     QemuOpts *opts;
1173 
1174     nc = qemu_find_netdev(id);
1175     if (!nc) {
1176         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1177                   "Device '%s' not found", id);
1178         return;
1179     }
1180 
1181     if (!nc->is_netdev) {
1182         error_setg(errp, "Device '%s' is not a netdev", id);
1183         return;
1184     }
1185 
1186     qemu_del_net_client(nc);
1187 
1188     /*
1189      * Wart: we need to delete the QemuOpts associated with netdevs
1190      * created via CLI or HMP, to avoid bogus "Duplicate ID" errors in
1191      * HMP netdev_add.
1192      */
1193     opts = qemu_opts_find(qemu_find_opts("netdev"), id);
1194     if (opts) {
1195         qemu_opts_del(opts);
1196     }
1197 }
1198 
1199 static void netfilter_print_info(Monitor *mon, NetFilterState *nf)
1200 {
1201     char *str;
1202     ObjectProperty *prop;
1203     ObjectPropertyIterator iter;
1204     Visitor *v;
1205 
1206     /* generate info str */
1207     object_property_iter_init(&iter, OBJECT(nf));
1208     while ((prop = object_property_iter_next(&iter))) {
1209         if (!strcmp(prop->name, "type")) {
1210             continue;
1211         }
1212         v = string_output_visitor_new(false, &str);
1213         object_property_get(OBJECT(nf), prop->name, v, NULL);
1214         visit_complete(v, &str);
1215         visit_free(v);
1216         monitor_printf(mon, ",%s=%s", prop->name, str);
1217         g_free(str);
1218     }
1219     monitor_printf(mon, "\n");
1220 }
1221 
1222 void print_net_client(Monitor *mon, NetClientState *nc)
1223 {
1224     NetFilterState *nf;
1225 
1226     monitor_printf(mon, "%s: index=%d,type=%s,%s\n", nc->name,
1227                    nc->queue_index,
1228                    NetClientDriver_str(nc->info->type),
1229                    nc->info_str);
1230     if (!QTAILQ_EMPTY(&nc->filters)) {
1231         monitor_printf(mon, "filters:\n");
1232     }
1233     QTAILQ_FOREACH(nf, &nc->filters, next) {
1234         monitor_printf(mon, "  - %s: type=%s",
1235                        object_get_canonical_path_component(OBJECT(nf)),
1236                        object_get_typename(OBJECT(nf)));
1237         netfilter_print_info(mon, nf);
1238     }
1239 }
1240 
1241 RxFilterInfoList *qmp_query_rx_filter(bool has_name, const char *name,
1242                                       Error **errp)
1243 {
1244     NetClientState *nc;
1245     RxFilterInfoList *filter_list = NULL, **tail = &filter_list;
1246 
1247     QTAILQ_FOREACH(nc, &net_clients, next) {
1248         RxFilterInfo *info;
1249 
1250         if (has_name && strcmp(nc->name, name) != 0) {
1251             continue;
1252         }
1253 
1254         /* only query rx-filter information of NIC */
1255         if (nc->info->type != NET_CLIENT_DRIVER_NIC) {
1256             if (has_name) {
1257                 error_setg(errp, "net client(%s) isn't a NIC", name);
1258                 assert(!filter_list);
1259                 return NULL;
1260             }
1261             continue;
1262         }
1263 
1264         /* only query information on queue 0 since the info is per nic,
1265          * not per queue
1266          */
1267         if (nc->queue_index != 0)
1268             continue;
1269 
1270         if (nc->info->query_rx_filter) {
1271             info = nc->info->query_rx_filter(nc);
1272             QAPI_LIST_APPEND(tail, info);
1273         } else if (has_name) {
1274             error_setg(errp, "net client(%s) doesn't support"
1275                        " rx-filter querying", name);
1276             assert(!filter_list);
1277             return NULL;
1278         }
1279 
1280         if (has_name) {
1281             break;
1282         }
1283     }
1284 
1285     if (filter_list == NULL && has_name) {
1286         error_setg(errp, "invalid net client name: %s", name);
1287     }
1288 
1289     return filter_list;
1290 }
1291 
1292 NetdevInfoList *qmp_query_netdev(Error **errp)
1293 {
1294     NetdevInfoList *list = NULL;
1295     NetClientState *nc;
1296 
1297     QTAILQ_FOREACH(nc, &net_clients, next) {
1298         /*
1299          * Only look at netdevs (backend network devices), not for each queue
1300          * or NIC / hubport
1301          */
1302         if (nc->stored_config) {
1303             NetdevInfo *element = QAPI_CLONE(NetdevInfo, nc->stored_config);
1304 
1305             g_free(element->id); /* Need to dealloc empty id after clone */
1306             element->id = g_strdup(nc->name);
1307 
1308             element->has_peer_id = nc->peer != NULL;
1309             if (element->has_peer_id) {
1310                 element->peer_id = g_strdup(nc->peer->name);
1311             }
1312 
1313             QAPI_LIST_PREPEND(list, element);
1314         }
1315     }
1316 
1317     return list;
1318 }
1319 
1320 void hmp_info_network(Monitor *mon, const QDict *qdict)
1321 {
1322     NetClientState *nc, *peer;
1323     NetClientDriver type;
1324 
1325     net_hub_info(mon);
1326 
1327     QTAILQ_FOREACH(nc, &net_clients, next) {
1328         peer = nc->peer;
1329         type = nc->info->type;
1330 
1331         /* Skip if already printed in hub info */
1332         if (net_hub_id_for_client(nc, NULL) == 0) {
1333             continue;
1334         }
1335 
1336         if (!peer || type == NET_CLIENT_DRIVER_NIC) {
1337             print_net_client(mon, nc);
1338         } /* else it's a netdev connected to a NIC, printed with the NIC */
1339         if (peer && type == NET_CLIENT_DRIVER_NIC) {
1340             monitor_printf(mon, " \\ ");
1341             print_net_client(mon, peer);
1342         }
1343     }
1344 }
1345 
1346 void colo_notify_filters_event(int event, Error **errp)
1347 {
1348     NetClientState *nc;
1349     NetFilterState *nf;
1350     NetFilterClass *nfc = NULL;
1351     Error *local_err = NULL;
1352 
1353     QTAILQ_FOREACH(nc, &net_clients, next) {
1354         QTAILQ_FOREACH(nf, &nc->filters, next) {
1355             nfc = NETFILTER_GET_CLASS(OBJECT(nf));
1356             nfc->handle_event(nf, event, &local_err);
1357             if (local_err) {
1358                 error_propagate(errp, local_err);
1359                 return;
1360             }
1361         }
1362     }
1363 }
1364 
1365 void qmp_set_link(const char *name, bool up, Error **errp)
1366 {
1367     NetClientState *ncs[MAX_QUEUE_NUM];
1368     NetClientState *nc;
1369     int queues, i;
1370 
1371     queues = qemu_find_net_clients_except(name, ncs,
1372                                           NET_CLIENT_DRIVER__MAX,
1373                                           MAX_QUEUE_NUM);
1374 
1375     if (queues == 0) {
1376         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
1377                   "Device '%s' not found", name);
1378         return;
1379     }
1380     nc = ncs[0];
1381 
1382     for (i = 0; i < queues; i++) {
1383         ncs[i]->link_down = !up;
1384     }
1385 
1386     if (nc->info->link_status_changed) {
1387         nc->info->link_status_changed(nc);
1388     }
1389 
1390     if (nc->peer) {
1391         /* Change peer link only if the peer is NIC and then notify peer.
1392          * If the peer is a HUBPORT or a backend, we do not change the
1393          * link status.
1394          *
1395          * This behavior is compatible with qemu hubs where there could be
1396          * multiple clients that can still communicate with each other in
1397          * disconnected mode. For now maintain this compatibility.
1398          */
1399         if (nc->peer->info->type == NET_CLIENT_DRIVER_NIC) {
1400             for (i = 0; i < queues; i++) {
1401                 ncs[i]->peer->link_down = !up;
1402             }
1403         }
1404         if (nc->peer->info->link_status_changed) {
1405             nc->peer->info->link_status_changed(nc->peer);
1406         }
1407     }
1408 }
1409 
1410 static void net_vm_change_state_handler(void *opaque, bool running,
1411                                         RunState state)
1412 {
1413     NetClientState *nc;
1414     NetClientState *tmp;
1415 
1416     QTAILQ_FOREACH_SAFE(nc, &net_clients, next, tmp) {
1417         if (running) {
1418             /* Flush queued packets and wake up backends. */
1419             if (nc->peer && qemu_can_send_packet(nc)) {
1420                 qemu_flush_queued_packets(nc->peer);
1421             }
1422         } else {
1423             /* Complete all queued packets, to guarantee we don't modify
1424              * state later when VM is not running.
1425              */
1426             qemu_flush_or_purge_queued_packets(nc, true);
1427         }
1428     }
1429 }
1430 
1431 void net_cleanup(void)
1432 {
1433     NetClientState *nc;
1434 
1435     /* We may del multiple entries during qemu_del_net_client(),
1436      * so QTAILQ_FOREACH_SAFE() is also not safe here.
1437      */
1438     while (!QTAILQ_EMPTY(&net_clients)) {
1439         nc = QTAILQ_FIRST(&net_clients);
1440         if (nc->info->type == NET_CLIENT_DRIVER_NIC) {
1441             qemu_del_nic(qemu_get_nic(nc));
1442         } else {
1443             qemu_del_net_client(nc);
1444         }
1445     }
1446 
1447     qemu_del_vm_change_state_handler(net_change_state_entry);
1448 }
1449 
1450 void net_check_clients(void)
1451 {
1452     NetClientState *nc;
1453     int i;
1454 
1455     net_hub_check_clients();
1456 
1457     QTAILQ_FOREACH(nc, &net_clients, next) {
1458         if (!nc->peer) {
1459             warn_report("%s %s has no peer",
1460                         nc->info->type == NET_CLIENT_DRIVER_NIC
1461                         ? "nic" : "netdev",
1462                         nc->name);
1463         }
1464     }
1465 
1466     /* Check that all NICs requested via -net nic actually got created.
1467      * NICs created via -device don't need to be checked here because
1468      * they are always instantiated.
1469      */
1470     for (i = 0; i < MAX_NICS; i++) {
1471         NICInfo *nd = &nd_table[i];
1472         if (nd->used && !nd->instantiated) {
1473             warn_report("requested NIC (%s, model %s) "
1474                         "was not created (not supported by this machine?)",
1475                         nd->name ? nd->name : "anonymous",
1476                         nd->model ? nd->model : "unspecified");
1477         }
1478     }
1479 }
1480 
1481 static int net_init_client(void *dummy, QemuOpts *opts, Error **errp)
1482 {
1483     return net_client_init(opts, false, errp);
1484 }
1485 
1486 static int net_init_netdev(void *dummy, QemuOpts *opts, Error **errp)
1487 {
1488     const char *type = qemu_opt_get(opts, "type");
1489 
1490     if (type && is_help_option(type)) {
1491         show_netdevs();
1492         exit(0);
1493     }
1494     return net_client_init(opts, true, errp);
1495 }
1496 
1497 /* For the convenience "--nic" parameter */
1498 static int net_param_nic(void *dummy, QemuOpts *opts, Error **errp)
1499 {
1500     char *mac, *nd_id;
1501     int idx, ret;
1502     NICInfo *ni;
1503     const char *type;
1504 
1505     type = qemu_opt_get(opts, "type");
1506     if (type && g_str_equal(type, "none")) {
1507         return 0;    /* Nothing to do, default_net is cleared in vl.c */
1508     }
1509 
1510     idx = nic_get_free_idx();
1511     if (idx == -1 || nb_nics >= MAX_NICS) {
1512         error_setg(errp, "no more on-board/default NIC slots available");
1513         return -1;
1514     }
1515 
1516     if (!type) {
1517         qemu_opt_set(opts, "type", "user", &error_abort);
1518     }
1519 
1520     ni = &nd_table[idx];
1521     memset(ni, 0, sizeof(*ni));
1522     ni->model = qemu_opt_get_del(opts, "model");
1523 
1524     /* Create an ID if the user did not specify one */
1525     nd_id = g_strdup(qemu_opts_id(opts));
1526     if (!nd_id) {
1527         nd_id = id_generate(ID_NET);
1528         qemu_opts_set_id(opts, nd_id);
1529     }
1530 
1531     /* Handle MAC address */
1532     mac = qemu_opt_get_del(opts, "mac");
1533     if (mac) {
1534         ret = net_parse_macaddr(ni->macaddr.a, mac);
1535         g_free(mac);
1536         if (ret) {
1537             error_setg(errp, "invalid syntax for ethernet address");
1538             goto out;
1539         }
1540         if (is_multicast_ether_addr(ni->macaddr.a)) {
1541             error_setg(errp, "NIC cannot have multicast MAC address");
1542             ret = -1;
1543             goto out;
1544         }
1545     }
1546     qemu_macaddr_default_if_unset(&ni->macaddr);
1547 
1548     ret = net_client_init(opts, true, errp);
1549     if (ret == 0) {
1550         ni->netdev = qemu_find_netdev(nd_id);
1551         ni->used = true;
1552         nb_nics++;
1553     }
1554 
1555 out:
1556     g_free(nd_id);
1557     return ret;
1558 }
1559 
1560 int net_init_clients(Error **errp)
1561 {
1562     net_change_state_entry =
1563         qemu_add_vm_change_state_handler(net_vm_change_state_handler, NULL);
1564 
1565     QTAILQ_INIT(&net_clients);
1566 
1567     if (qemu_opts_foreach(qemu_find_opts("netdev"),
1568                           net_init_netdev, NULL, errp)) {
1569         return -1;
1570     }
1571 
1572     if (qemu_opts_foreach(qemu_find_opts("nic"), net_param_nic, NULL, errp)) {
1573         return -1;
1574     }
1575 
1576     if (qemu_opts_foreach(qemu_find_opts("net"), net_init_client, NULL, errp)) {
1577         return -1;
1578     }
1579 
1580     return 0;
1581 }
1582 
1583 int net_client_parse(QemuOptsList *opts_list, const char *optarg)
1584 {
1585     if (!qemu_opts_parse_noisily(opts_list, optarg, true)) {
1586         return -1;
1587     }
1588 
1589     return 0;
1590 }
1591 
1592 /* From FreeBSD */
1593 /* XXX: optimize */
1594 uint32_t net_crc32(const uint8_t *p, int len)
1595 {
1596     uint32_t crc;
1597     int carry, i, j;
1598     uint8_t b;
1599 
1600     crc = 0xffffffff;
1601     for (i = 0; i < len; i++) {
1602         b = *p++;
1603         for (j = 0; j < 8; j++) {
1604             carry = ((crc & 0x80000000L) ? 1 : 0) ^ (b & 0x01);
1605             crc <<= 1;
1606             b >>= 1;
1607             if (carry) {
1608                 crc = ((crc ^ POLYNOMIAL_BE) | carry);
1609             }
1610         }
1611     }
1612 
1613     return crc;
1614 }
1615 
1616 uint32_t net_crc32_le(const uint8_t *p, int len)
1617 {
1618     uint32_t crc;
1619     int carry, i, j;
1620     uint8_t b;
1621 
1622     crc = 0xffffffff;
1623     for (i = 0; i < len; i++) {
1624         b = *p++;
1625         for (j = 0; j < 8; j++) {
1626             carry = (crc & 0x1) ^ (b & 0x01);
1627             crc >>= 1;
1628             b >>= 1;
1629             if (carry) {
1630                 crc ^= POLYNOMIAL_LE;
1631             }
1632         }
1633     }
1634 
1635     return crc;
1636 }
1637 
1638 QemuOptsList qemu_netdev_opts = {
1639     .name = "netdev",
1640     .implied_opt_name = "type",
1641     .head = QTAILQ_HEAD_INITIALIZER(qemu_netdev_opts.head),
1642     .desc = {
1643         /*
1644          * no elements => accept any params
1645          * validation will happen later
1646          */
1647         { /* end of list */ }
1648     },
1649 };
1650 
1651 QemuOptsList qemu_nic_opts = {
1652     .name = "nic",
1653     .implied_opt_name = "type",
1654     .head = QTAILQ_HEAD_INITIALIZER(qemu_nic_opts.head),
1655     .desc = {
1656         /*
1657          * no elements => accept any params
1658          * validation will happen later
1659          */
1660         { /* end of list */ }
1661     },
1662 };
1663 
1664 QemuOptsList qemu_net_opts = {
1665     .name = "net",
1666     .implied_opt_name = "type",
1667     .head = QTAILQ_HEAD_INITIALIZER(qemu_net_opts.head),
1668     .desc = {
1669         /*
1670          * no elements => accept any params
1671          * validation will happen later
1672          */
1673         { /* end of list */ }
1674     },
1675 };
1676 
1677 void net_socket_rs_init(SocketReadState *rs,
1678                         SocketReadStateFinalize *finalize,
1679                         bool vnet_hdr)
1680 {
1681     rs->state = 0;
1682     rs->vnet_hdr = vnet_hdr;
1683     rs->index = 0;
1684     rs->packet_len = 0;
1685     rs->vnet_hdr_len = 0;
1686     memset(rs->buf, 0, sizeof(rs->buf));
1687     rs->finalize = finalize;
1688 }
1689 
1690 /*
1691  * Returns
1692  * 0: success
1693  * -1: error occurs
1694  */
1695 int net_fill_rstate(SocketReadState *rs, const uint8_t *buf, int size)
1696 {
1697     unsigned int l;
1698 
1699     while (size > 0) {
1700         /* Reassemble a packet from the network.
1701          * 0 = getting length.
1702          * 1 = getting vnet header length.
1703          * 2 = getting data.
1704          */
1705         switch (rs->state) {
1706         case 0:
1707             l = 4 - rs->index;
1708             if (l > size) {
1709                 l = size;
1710             }
1711             memcpy(rs->buf + rs->index, buf, l);
1712             buf += l;
1713             size -= l;
1714             rs->index += l;
1715             if (rs->index == 4) {
1716                 /* got length */
1717                 rs->packet_len = ntohl(*(uint32_t *)rs->buf);
1718                 rs->index = 0;
1719                 if (rs->vnet_hdr) {
1720                     rs->state = 1;
1721                 } else {
1722                     rs->state = 2;
1723                     rs->vnet_hdr_len = 0;
1724                 }
1725             }
1726             break;
1727         case 1:
1728             l = 4 - rs->index;
1729             if (l > size) {
1730                 l = size;
1731             }
1732             memcpy(rs->buf + rs->index, buf, l);
1733             buf += l;
1734             size -= l;
1735             rs->index += l;
1736             if (rs->index == 4) {
1737                 /* got vnet header length */
1738                 rs->vnet_hdr_len = ntohl(*(uint32_t *)rs->buf);
1739                 rs->index = 0;
1740                 rs->state = 2;
1741             }
1742             break;
1743         case 2:
1744             l = rs->packet_len - rs->index;
1745             if (l > size) {
1746                 l = size;
1747             }
1748             if (rs->index + l <= sizeof(rs->buf)) {
1749                 memcpy(rs->buf + rs->index, buf, l);
1750             } else {
1751                 fprintf(stderr, "serious error: oversized packet received,"
1752                     "connection terminated.\n");
1753                 rs->index = rs->state = 0;
1754                 return -1;
1755             }
1756 
1757             rs->index += l;
1758             buf += l;
1759             size -= l;
1760             if (rs->index >= rs->packet_len) {
1761                 rs->index = 0;
1762                 rs->state = 0;
1763                 assert(rs->finalize);
1764                 rs->finalize(rs);
1765             }
1766             break;
1767         }
1768     }
1769 
1770     assert(size == 0);
1771     return 0;
1772 }
1773